1. Field of the Invention
The present invention relates to a method for estimating the background energy level of a signal. More specifically, the present invention relates to a method for efficient estimation of the background energy of a signal which contains both background and information.
2. Discussion of Related Art
Signals which carry information, including communication signals carrying voice information, often contain a background level of energy or noise in the signal. Background noise can originate from a number of sources, including environmental noise at the origin of the signal or noise induced by a signal carrier. It is often desirable to identify background noise, and such identification can be used in a number of ways when working with an information signal. In communications, it is also desirable to eliminate this background noise to provide a cleaner signal to the recipient, to reduce the overall energy of the signal, or to aid in the identification of echo of other signal anomalies such as double talk and reduce the error rate in transmission. Also, incorrect estimation and compensation for background noise can effect error checking in a digital signal. The background noise determination can also be useful in determining the parameters for the introduction of comfort noise, if desirable.
Background noise can be identified by analysis of the characteristics of the signal. The characteristics of a signal can be evaluated to distinguish noise from other information such as speech. Algorithms for identification of signal characteristics can be complex and require substantial processing power and time. Often a delay must be introduced in order to process the signal for complex recognition and to distinguish speech from noise.